AverageFinder - AverageFinder is an all-in-one product value tracking service for eBay that will provide all the information related to product selling and purchasing.

AliPrice - AliExpress Price Tracker app lets you track the price history of any item from many online retailers like AliExpress, Daraz, and Amazon, etc.

Altosight - eCommerce price monitoring & tracking software

idealo - Idealo is a free to use mobile application that helps you to find products, compare price and make an informed decision.

PRICEFY.IO - Monitor your competitors' products and prices with ease. No single URLs to paste or proxies to rotate, just put your competitor's domain and monitor his product's price daily.

Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.